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MISCELLANEOUS PAPERS. 



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Cal. At the latter place many entered hibernation as early as Octo- 

 ber 5, and after that date very few adults emerged. 



OCCURRENCE. 



The adult of this insect was first observed in a bean field at Holly- 

 wood, Cal., on June 29, 1911. At this time one was noted in ovipo- 

 sition and a careful search of the bean foliage for about 3 hours 

 resulted in the capture of 5 more. On July 18, 1911, Mr, Graf and 

 the writer again visited this field and after a very careful examination 

 collected 12 more adults. On August 4, 1911, a visit to this field 

 resulted in the capture of 7 more specimens of this insect, and on 

 August 18 a prolonged examination produced 1 specimen on a leaf 



of Lactuca scariola and 1 on the 

 leaf of a lima bean plant. 



At Compton, although many 

 parasitized thrips had been col- 

 lected for over 1^ months, tliis 

 insect was not found in the adult 

 stage until August 26, 1911, when 

 1 was taken on a leaf of Lactuca. 

 At this time the adults seemed to 

 be very common on turnips in the 

 laboratory yard, for on August 

 28 Mr. Graf collected 1; on August 

 29, 1; and on August 30, 2. The 

 writer, on September 1, observed 

 7 adults crawling over turnip foliage and on September 2, 4 more were 

 observed . Two of these were actively ovipositing in larvae of Thrips 

 tahaci. On September 17 and 23 Mr. Graf observed 4 adults on the 

 turnip foliage. 



While Mr. Graf was at Puente, Cal., on October 3, 1911, he found 

 1 adult of this parasite on a leaf of SoncJius oleraceus badly infested 

 by the bean thrips. At the same place on October 21, 1911, Mr. 

 Graf discovered a small bush of Nicotiana glauca badly infested by 

 the larvae of Heliothrips fasciatus and careful examination revealed 

 the presence of this insect. On 15 leaves of this plant infested by 

 the bean thrips he found between 40 and 50 adults of this parasite. 

 These were very active and many were observed in oviposition. 



DISTRIBUTION. 



This insect was first discovered at Compton, Cal., during Decem- 

 ber, 1910, and during 1911 it has been found to occur very commonly 

 in that locality. During June, 1911, it was found to occur at Holly- 

 wood and later it was reared from material collected at Wliittier and 

 Puente, Cal. These locahties are all situated in Los Angeles County 

 and make up an area of nearly 150 square miles. A few collections 



Fig. 9. — Diagram illustrating length of time from 

 oviposition to pupation for 241 individuals of 

 Thripoctenus russclU. (Original.) 



